The present invention is directed to bicycle brake devices and, more particularly, to bicycle brake devices that are used to brake a hub of a bicycle wheel.
Bicycle braking devices currently available include rim braking devices and hub braking devices. Rim braking devices include cantilever brakes or caliper brakes that brake the rim of the wheel. Hub braking devices brake the wheel hub, and they include drum brakes, band brakes, roller brakes and the like. A hub brake brakes the hub of the wheel, so it is able to provide braking even if the wheel rim is warped.
Conventional bicycle hub brake devices comprise a fastening bracket nonrotatably mounted to the bicycle frame, a brake drum that rotates integrally with the hub, a brake member such as a brake shoe or a brake band that provide a braking action on the brake drum, and a brake operating component for bringing the brake shoes into pressed contact with the braking surface of the brake drum.
The fastening bracket has a base section through which the hub shaft passes and that is secured to the hub shaft, an arm section that extends essentially radially from the base section, and a lock section that is formed on the distal end of the arm section. The lock section serves to mount the hub brake device to the bicycle frame, and it is mounted and secured to a bracket fastening member that is fastened to the front fork or the chainstay of the bicycle, for example.
The bracket fastening member may be of the type that is welded to the frame and serves to lock the fastening bracket in place. Alternatively, the bracket fastening member may be of the type that removably fastens the fastening bracket to the frame. If the bracket fastening member is removably fastened to the frame, a tool must be used in order to remove the bracket fastening member when mounting or removing the wheel. This is very inconvenient, especially when a quick-release hub that permits easy replacement of the wheel is used. As a result, in many cases a welded-on bracket fastening member is used to lock the fastening bracket.
A bracket fastening member that is intended to be welded to the frame is normally supplied by the brake manufacturer to the bicycle manufacturer together with the hub brake device. A locking space is formed in the center of the bracket fastening member for receiving the lock section of the fastening bracket therein to thereby lock the fastening bracket to the frame. In order to be compatible with the frame, and particularly with different orientations and configurations of the front fork, this locking space is formed such that it has an hourglass-like cross-sectional configuration in which the opening area into which the lock section is inserted and the exit area from which the lock section emerges are wider than the center area.
In the conventional mounting construction described above, a gap may exist between the lock section and the locking space when the lock section is disposed in the locking space due to erroneous mounting of the bracket securing member or the like. If a gap exists in the hub axial direction or the rotational direction, there is a danger that the hub brake device will rattle and make noise when the brake is applied.